The female athlete triad

Young female athletes may be at risk of three interrelated conditions, including lack of adequate calories, menstrual abnormalities and weak bones.

For girls and young women who compete at the highest levels of sports, their days consist primarily of school, homework and practice. These athletes are nothing if not busy. Their parents are as well, often shuttling the girls from practice to practice and then driving them to multiple competitive events a week — some near, some far.

Amid the hustle, it's easy to forget or glide over things such as eating good meals, getting enough sleep, finding time to relax and keeping up with medical checkups. But for elite young female athletes, these habits are incredibly important for both immediate and long-term health and development. They're also key to avoiding the risks of what's known as the female athlete triad.

Components of the triad

The female athlete triad describes three interrelated conditions that tend to occur more often among female athletes than nonathletes. The three conditions are:

Low energy availability. When girls and young women don't take in enough calories to compensate for those expended during exercise, the result is an energy deficiency. Doing this once or twice is no big deal. But persistently shortchanging the body's energy account can lead to a state of low energy availability. The result? The body lacks the fuel it needs to function and develop properly. Young women might reach this point inadvertently — they just don't think about the health costs of skipping meals, or they forget or are too tired. Some girls restrict what they eat intentionally, often in an effort to achieve a competitive weight or a certain aesthetic look. Some other girls and young women could have an eating disorder. In any case, not getting enough calories sets the stage for the other two conditions of the triad.

Menstrual dysfunction. When a girl's body is running low on energy, the body adopts various energy-conservation measures, including in the reproductive system. Hormone production is suppressed, which can lead to a delay in beginning menstruation, irregular periods or no periods at all. Not having a period can seem like a boon at first, but a lack of hormones such as estrogen can contribute to loss of bone density, as well as problems that become more apparent later in life, such as infertility.

Weak bones. Adolescence is the most important time to accumulate bone mass. Not getting enough calories — including nutrients that are key to bone health — can disrupt bone formation at this critical juncture. The physical and emotional stress of high-intensity training and inadequate calories also can cause changes in estrogen, growth hormone and cortisol production. These disruptions correlate with decreased bone mass. In the short term, weak bones make young female athletes more vulnerable to stress fractures and other injuries. And if young women don't achieve full bone mass in these younger years, they will be at greater risk of having weak and brittle bones (osteoporosis) and fractures later in life.

One size doesn't fit all

The female athlete triad is generally not a straightforward diagnosis. Although girls and young women who participate in sports are at increased risk, not all of them develop the three conditions. Many young female athletes will experience one or two components of the triad, rather than all three, often with varying levels of severity and evolving patterns over time. For example, the prevalence of eating disorders among female athletes — which is accompanied by low energy availability — can range anywhere from 1 to 62 percent depending on the type of sport. Rates of eating disorders are higher among female athletes whose sports emphasize leanness and aesthetics, such as dance, cheerleading and figure skating.

The female athlete triad is best described as a spectrum. On one end are optimal energy availability, normal menstrual function and optimal bone health. At the other end are low energy availability (with or without an eating disorder), complete absence of menstruation and osteoporosis. Young female athletes do not have to be on the extreme end of the spectrum to need help. In fact, the sooner treatments start along the spectrum, the better the long-term health outcomes will be.

Parents and coaches need to be able to recognize signs that are typically part of the triad:

Eating disorders, such as bulimia or anorexia

Body image concerns

Stress fractures

Frequent dieting

Menstrual irregularities

Excessive exercise

Obsessive or perfectionist behavior

Food as fuel

The linchpin of the female athlete triad is energy availability. A nutritious diet with enough calories, balanced with appropriate levels of training, is the most important component for staying on the healthy end of the spectrum. The message for young female athletes is simple but powerful: Food is fuel for your growing body and for achieving your best performance.

Supportive adults — parents and coaches in particular — also have a role to play in helping girls recognize signs of a problem. Seeking help should never be portrayed or viewed as a sign of weakness when, in fact, it can help girls and young women become better athletes. In some cases, the help of a mental health professional can be very valuable. And girls and young women who are diagnosed with eating disorders should receive comprehensive care from a multidisciplinary team, because the consequences can be severe and even fatal when not addressed. Ultimately, young women should appreciate that their health, well-being and roles in life extend beyond their identity as athletes.

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